The present invention relates generally to an adjustable seat for watercraft such as kayaks or canoes and the like. The invention is particularly adapted for use in either closed or open cockpit kayaks.
Conventional seats for kayaks include a substantially horizontal support for the buttocks with an integral, substantially vertical back support. Other known seats have a tiltable back support which can be separately inclined relative to the horizontal support. Such seats are often constructed of molded plastic and are contoured to conform to the general shape of a person""s buttocks and lower back. These seats may include padding for added comfort. A conventional kayak seat is fixed to an inside surface of a kayak hull so that a person""s buttocks are at the same general elevation as the person""s feet, which extend forward of the seat. Adjustable foot pegs are often included along the inner gunwales of the kayak to provide longitudinal support for a person""s feet in the kayak. Normally, a person will position the foot pegs relative to the seat so that the person""s legs are bent, with the person""s knees elevated above the bottom of the cockpit. This arrangement provides firm support for a person paddling in the kayak and enables a person to use his or her legs and body to assist in controlling the kayak""s attitude and movement in the water.
However, conventional kayak seats are generally designed for those paddlers who desire the lowest possible leg position and/or for paddlers having large thighs. As a result, the majority of kayak seats do not provide adequate support for most paddlers. Because the preferred bent-knee position causes a paddler""s thighs to be elevated above the forward portions of the pelvic support in such seats, a paddler""s upper thighs are substantially unsupported. This lack of thigh support can accelerate the fatigue experienced in a paddler""s legs and can contribute to excessive pressure on a paddler""s sciatic nerve at the point where the nerve exits the hip. Irritation of the sciatic nerve is one of the more common ailments affecting paddlers. Excessive pressure on a paddler""s sciatic nerve can cause numbness or discomfort in a paddler""s lower leg or foot, pain in a paddler""s calf, and/or pain down the back of a paddler""s legs.
In addition, the back support in such seats is typically fixed at a set height with respect to the pelvis support. For a paddler, a properly fitted back support should be positioned so that it provides the optimal comfort for an individual paddler. While inclining a backrest helps, vertical height adjustment of the backrest is necessary to accommodate the natural variation in spinal curvatures between various individuals. The spinal areas for support are the lumbar area and the thoracic area of the spine. The lumbar area is concave and the thoracic area is convex. A properly fitted back support will support a portion of the lumbar area and a portion of the thoracic area. Specifically, it should support a portion of the concave lumbar area and a portion of spine that is between the concave lumbar area and convex thoracic area of the spine.
Existing seats for small watercraft include tilt but not height adjustability for providing optimal variable back support for persons having differing body shapes and sizes or having varying preferences for paddling positions. The lack of optimal back support can contribute to fatigue and decrease a person""s enjoyment of the boating activity.
Others have attempted to address these shortcomings in various ways. For example, U.S. Pat. No. 6,112,693 to Addison discloses a kayak seat with means for adjusting the height of a seat relative to the water line in a kayak. This patent describes a rigid seat which may be elevated using blocks or a linkage beneath the seat, and an adjustment means for raising the front of the seat more or less than the back of the seat to accommodate differences in paddler build. However, the disclosed adjustment means requires lifting and/or tilting the entire rigid seat, and does not provide for independent adjustments for improved thigh support and optimal back support. In addition, incremental adjustment of the seat for various paddlers is difficult and cannot be readily accomplished while a paddler is seated in the seat.
U.S. Pat. No. 5,970,903 to McDonough et al. discloses a kinesthetic kayak cockpit seat which includes a body-fitting molded seat with a removable back support. However, this patent does not provide an adjustable thigh support or back support which can be independently adapted to a particular person""s body size and shape.
Wilderness Systems Inc. of Trinity, N.C. produces and sells a kayak seat back extension (Product No. 1595-0100) for extending the total height of a seat back on a kayak seat. The extension includes a support pad with a pocket that slips over the top of a standard seatback. While this extension provides higher or greater back support and comfort for paddlers, it provides only two discrete seatback heights that may not be optimal for some persons.
Thus, there remains a need for a new and improved seat for small watercraft which can be quickly and easily adjusted to comfortably support the thighs of persons of varying sizes and shapes and to accommodate persons having varying preferences for paddling positions in a watercraft. There is a similar need for a backrest which is adjustable in height.
The present invention fulfills this need in the art by providing a seat for watercraft that provides adjustable support for key areas of a person""s body while seated in the seat. Accordingly, one aspect of the present invention is to provide a seat for a watercraft comprising a pelvis support and a thigh support, wherein the thigh support is independently and separately positionable with respect to the pelvis support. Preferably, the thigh support is pivotally connected to the pelvis support. A means for fixing the thigh support in a desired position with respect to the pelvis support is provided. The fixing means may include one or more straps suspending the thigh support from one or more fixed portions of a watercraft containing the seat. Alternatively, one or more straps may suspend the thigh support from a back support on the seat. In either embodiment, a strap adjustment means is provided for shortening or lengthening the strap or straps for suspending the thigh support at a desired position relative to the pelvis support. Because the strap adjustment means is forward of the back support, adjustment of the straps can be accomplished while a person is fully seated in the seat.
The invention also includes other means for fixing the position of the thigh support. An inflatable bladder under the thigh support can be inflated or deflated to alter the position of the thigh support relative to the pelvis support. A manual pump may be included for inflating the bladder, and a valve provided for deflating the bladder. Optionally, one or more wedges or blocks may be placed under the thigh support, or a ratcheting support may be provided to fix the thigh support in a desired position.
To maximize the comfort of the seat, the pelvis support and thigh support are preferably shaped so that the connected pelvis support and the thigh support combine to form a composite seating surface that approximates the contour of a seated person""s buttocks and thighs over a range of thigh support positions relative to the pelvis support.
Preferably, the pelvis support and thigh support are molded plastic.
Another aspect of the present invention is to provide a seat for a watercraft having a pelvis support and a vertically adjustable back support which is incrementally adjustable between a lowest backrest position and a highest backrest position. The back support may adjust in angular orientation with respect to the pelvis support. For example, a post may be pivotally mounted to the pelvis support, and one or more adjustable belts attached to the back support and adapted for connection to a fixed portion of a watercraft containing the seat for adjusting and fixing an inclination of the back support relative to the pelvis support.
In addition, the back support includes a backrest that adjusts in height with respect to the pelvis support. A post may be connected to the pelvis support and have a backrest movably engaged on the post. The post may be pivotally connected to the pelvis support. Preferably, a backrest adjustment means is provided for elevating or lowering the backrest on the post. Such adjustment means may be remotely operable by a forward-facing person seated in the seat. One or more resilient members may be provided to bias the backrest downwardly on the post.
In a preferred arrangement, the backrest adjustment means includes an upper pulley or guide on the post near its top end, a lower pulley or guide on the post near its lower end, a rope having a fixed end and a free end, and a cleat beneath a forward portion of the pelvis support. The fixed end of the rope is attached to the backrest and the rope extends over the upper pulley or guide, under the lower pulley or guide, and under the pelvis support. The free end of the rope extends through the cleat forward of the pelvis support. The elevation of the backrest can be adjusted upwardly or downwardly by a person fully seated in the seat by pulling or feeding the free end of the rope through the cleat and engaging the rope in the cleat when the backrest is at a desired elevation.
Alternatively, the backrest adjustment may include a clamping means for clamping the backrest to the post at a desired elevation. The clamping means may include a backrest clamping surface on the backrest, a threaded rod extending outward from the backrest clamping surface, a post clamping surface having a slot for receiving the threaded rod, and a knob having a threaded hole for engagement on the threaded rod. The threaded rod on the backrest passes through the slot in the post and moves in the slot as the backrest is vertically positioned on the post. The backrest is clamped to the post by screwing the knob onto the threaded rod, thereby pressing the two clamping surfaces together. This arrangement may further include sawtooth ridges on the backrest clamping surface and mating saw tooth ridges on the post clamping surface, wherein the saw tooth ridges on the two surfaces positively engage one another when the backrest is clamped to the post.
Still another aspect of the present invention is to provide a seat having both an adjustable thigh support and an adjustable back support as described above. The invention also includes a canoe, kayak, or sit-on-top kayak equipped with a seat having an adjustable thigh support and/or adjustable back support as summarized above.
The invention further includes a method of boating comprising sitting in a seat having a thigh support located in a watercraft and adjusting the thigh support to a desired position while seated in the seat. The invention also includes a method of boating comprising sitting in a seat in a watercraft having a buttocks support and a back support pad that is vertically adjustable to multiple locations above the buttocks support, and adjusting the back support pad to a desired position while seated in the seat. Also, the invention includes a method of boating including sitting in a seat in a watercraft having a separately adjustable thigh support and back support, and adjusting the thigh support and back support to desired positions while fully seated in the seat. The above methods further include making the adjustment or adjustments as the watercraft moves on a body of water.
These and other aspects of the present invention will become apparent to those skilled in the art after a reading of the following description of the preferred embodiments when considered with the drawings.